Article

Discrepancy between the composition of some commercial cat foods and their package labelling and suitability for meeting nutritional requirements

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Abstract

Objective: To investigate if the label information and nutrient composition of commercial cat foods are accurate and compliant with the Australian Standard (AS 5812-2011) and if they meet the nutritional requirements of an adult cat. Methods: A chemical analysis of 10 wet and 10 dry commercial cat foods labelled as 'nutritionally complete' for the adult cat was performed. The results were compared with the package composition values, the Australian Standard and the unique dietary requirements of the cat. In addition, the results of the chemical analysis were compared with the nutrient requirements published by the Association of the American Feed Control Officials and the National Research Council. Results: When compared with the Australian Standard, 9 of the 20 cat foods did not adhere to their 'guaranteed analysis' and 8 did not adhere to the standards for nutrient composition. Also, various deficiencies and excesses of crude protein, crude fat, fatty acid and amino acid were observed in the majority of the cat foods. Conclusions: The results of this study highlight a need for an improved method of ensuring that label information and nutrient composition are accurate and comply with the Australian Standard (AS 5812-2011) to ensure the adult cat's unique dietary requirements are being met by commercial adult cat food.

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... In this and other studies, it is common to see that the amounts of some essential elements, selenium and manganese among them, are usually over-supplemented, sometimes exceeding the established legal limits [36,37]. In that sense, our results agree with others already published, highlighting the existing discrepancies between what the pet industry says that a food provides and what it really has in terms of essential elements The fact that only a minority of brands comply with all nutrient content claims listed on their labels [38,39] indicates that the need for legislation in this regard is urgent. Apart from not complying with the legislation related to labels and being, at times, misleading advertising, in certain circumstances the health of the pets themselves can even be put at risk. ...
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Kohlenhydratstoffwechsel der Katze 2. Verdauung von Stärke In 6 Verdauungsversuchen und 5 post-mortem-Experimenten erhielten 56 erwachsene Katzen Rationen mit verschiedenen Stärkearten (gekochte Maisstärke = MSc, rohe Maisstärke = MSr, rohe Kartoffelstärke = PSr, Stärkeaufnahme 4,7–8,9 g/kg Körpermasse). Als kohlenhydratfreie Kontrollrationen dienten 2 fettreiche (FATc und FATr) und eine eiweißreiche Ration (PROT). Neben der Verdaulichkeit der Stärke (insgesamt und praecaecal) wurde der Einfluß der Stärke auf die Protein- und Fettverdauung sowie auf das intestinale und faecale Milieu (pH, Trockensubstanz, Osmolarität, organische Säuren, Pufferkapazität, Ammoniak, in-vitro-Gasbildungsvermögen) geprütt. In einem weiteren Versuchsansatz wurde der Einfluß der Darmflora durch hochdosierte orale Antibiotika (500 mg Ampicillin, 75 mg Clindamycin, 12,5 mg Enrofloxacin/Tier/d) weitgehend ausgeschaltet. Die Stärkeverdaulichkeit betrug bei MSc beinahe 100%, bei MSr 78% und bei PSr nur 36%. Die praecaecale Stärkeverdaulichkeit (post mortem durch Marker ermittelt) war niedriger als die Gesamtverdaulichkeit, es ergab sich jedoch eine ähnliche Abstufung (MSc 72, MSr 46, PSr 0%). Bei den Rationen mit roher Stärke (MSr und PSr) ging die Proteinverdaulichkeit zurück, während die Fettverdaulichkeit zunahm. Die Aufnahme von Stärke führte zu einer Säuerung des Chymus. Dieser Effekt wurde durch orale Antibiose deutlich gemildert. Die Konzentration der organischen Säuren im Chymus bzw. Kot wurde sowohl durch Stärke als auch durch orale Antibiose beeinflußt. Das in-vitro-Gasbildungsvermögen des Kotes war nach Stärkefütterung signifikant gröfier.
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Koblenhydratstoffwechsel der Katze 1. Aktivität der Amylase im Verdauungskanal Erwachsene Katzen erhielten entweder eine von 3 verschiedenen stärkereichen Rationen (gekochte bzw. rohe Maisstärke, rohe Kartoffelstärke, 30–37% Stärke in der Trockensubstanz) oder eine kohlenhydratfreie Kontrollration. In Pancreas, Chymus und Faeces wurde die Aktivität der Amylase bestimmt. Außerdem erfolgte eine Charakterisierung der Amylase aus Pancreasgewebe und Kot (pH-Optimum, Bindung an Partikel, Aktivität im Bakteriensediment, Säurestabilität, Einfluß von in-vitro-Fermentation). In einem weiteren Versuchsdurchgang wurde der Effekt oraler Antibiose (500 mg Ampicillin, 75 mg Clindamycin, 12,5 mg Enrofloxacin/Tier/d) auf die Amylaseaktivität im Kot überprüft. Chymotrypsin wurde in Chymus, Kot und nach in-vitro-Fermentation bestimmt. Die Aktivität der Amylase im Pancreas und Chymus war relativ gering (Pancreas 75 U/g, Dun̈ndarmchymus 10–50 U/g Frischgewicht). Es trat nur ein geringer Induktionseffekt durch Stärke im Futter auf, nach sehr langfristiger Stärkefütterung verdoppelte sich die Aktivität im Dünndarm. Die Amylaseaktivität nahm nach caudal ab. Die große Ähnlichkeit der faecalen Amylase mit der Pancreasamylase bei der Charakterisierung, das Ausbleiben einer systematischen Veränderung der Aktivität im Kot bei oraler Antibiose sowie der Rückgang bei in-vitro-Fermentation sprechen dafür, daß der überwiegende Teil der Amylase im Verdauungskanal der Katze aus dem Pancreas stammt.
Article
ZusammenfassungKohlenhydratstoffwechsel der Katze. 3. Verdauung von ZuckernAn 12 erwachsenen Katzen wurde die Gesamtverdaulichkeit von Glucose (5,1 g/kg Körpermasse), Galactose (5,6 g/kg Körpermasse), Lactose (1,3 und 4,5 g/kg Körpermasse) und Saccharose (7,2 g/kg Körpermasse) sowie die praecaecale Verdaulichkeit von Lactose und Saccharose (post-mortem-Versuche mit Chromoxid als Marker) ermittelt. Außerdem wurde der Einfluß dieser Zucker auf die Protein- und Fettverdaulichkeit sowie den Intestinalstoffwechsel (Wasser, pH-Wert, organische Suren) überprüft. Die Gesamtverdaulichkeit der Zucker betrug in allen Fllen nahezu 100%, die praecaecale Verdaulichkeit von Lactose in der höheren Dosierung 70,5 und von Saccharose 98,8%. Die scheinbare Verdaulichkeit des Proteins wurde durch Saccharose oder Lactose (beide Dosierungen) im Vergleich zur kohlenhydratfreien Kontrollgruppe um 4 bis 5% verringert. Glucose und Galactose übten keinen signifikanten Effekt auf den Kot-pH-Wert aus (Glucose 7,15, Galactose 6,96, kohlenhydratfrei 7,22), die anderen Zucker bewirkten jedoch eine mehr oder weniger starke Ansuerung der Faeces (Saccharose 6,00, Lactose, höhere Dosis 5,36, kleinere Dosis 6,38). Der pH-Wert im Magen und Dünndarm wurde durch Zuckerfütterung nicht verndert, im Dickdarm traten nach Lactose- bzw. Saccharoseaufnahme jedoch hnliche Effekte auf wie im Kot. Außer bei Saccharose ging der Gehalt an kurzkettigen Fettsuren (SCFA) im Kot nach Zuckeraufnahme zurück, whrend die Lactatkonzentration anstieg. Diese Vernderungen waren bei der hohen Lactosedosis am deutlichsten ausgeprgt (kohlenhydratfreie Ration: SCFA 307, Lactat 0,71 mmol/kg Kot; Lactose: SCFA 58, Lactat 14,27 mmol/kg). Whrend der Trockensubstanzgehalt im Kot nach Aufnahme von Monosacchariden anstieg, führten Disaccharide zu einer mehr oder weniger starken Zunahme des Wassergehaltes. Lactose und Saccharose bewirkten im Dünn- und Dickdarm ebenfalls einen Rückgang des Trockensub-stanzgehaltes im Chymus.
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The activities of three urea cycle enzymes, several nitrogen catabolic, gluconeogenic, and lipogenic enzymes were measured in the liver of adult cats fed: a commercial kibble; a 17.5 or 70% protein purified diet, or starved for 5 days. Except for an increase in tyrosine transaminase (EC 2.6.1.5) after feeding the high protein diet, there were no changes in the activities of the hepatic enzymes as influenced by dietary protein level. Likewise, starvation had a minimal effect on the activities of these enzymes as compared to that found in similar experiments in rats. These results indicate that the cat may have only minimal capabilities for enzyme adaptation as compared to that found in many herbivores and omnivores and may provide an explanation as to why cats have an unusually high protein requirement as compared to many other mammals.
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Cats fed a diet containing linoleate as the only polyunsaturated fatty acid showed extremely low levels of arachidonate in the plasma lipids, as well as an increase in linoleate, eicosadienoate and an unknown fatty acid. Administration of [1-14C]linoleic acid and [2-14C]eicosa-8,11,14-trienoic acid to cats showed that in the liver there was no conversion of the [1-14C] 18:2 to arachidonate, whereas there was significant metabolism of [2-14C] 20:3 to arachidonate. It was found when methyl-gamma-linolenate was fed to cats that the level of 20:3 omega 6 and 20:4 omega 6 in the erythrocytes increased significantly. These results show that there is no significant delta 6 desaturase activity in the cat, whereas chain elongation and delta 5 desaturase enzymes are operative. The unknown fatty acid was isolated from the liver lipids and shown to be a 20-carbon fatty acid with 3 double bonds and which by gas liquid chromatography could be separated from 20:3 omega 9 and 20:3 omega 6. The presence of the delta 5-desaturase activity and the results of the ozonolysis studies indicated that this unknown fatty acid was eicosa-5,11,14-trienoic acid.
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The reproductive performance and outcome of kittens was determined for female cats fed 0.05, 0.2 or 1% taurine. No adverse effects of high taurine diets were noted in the adults or offspring, and the reproductive performance was slightly better than that of females fed the normal (0.05% taurine) diet. Body weight at birth and brain weight at weaning were significantly greater in the very high taurine group than in the normal taurine group, although the greatest growth rate was achieved by the normal taurine group. The concentration of taurine in milk of lactating females was substantially higher in cats fed the higher taurine diets. Brain of adult cats was resistant to increases in brain taurine concentrations, as was brain of newborn cats. However, brain of juvenile cats responded to higher dietary taurine intake with increased taurine concentrations. These results indicate that the higher taurine content in cat foods recently introduced for prevention of feline dilated cardiomyopathy should have no adverse effects over a prolonged period on health and reproduction of cats.
Cats were fed 17.5% (LP) and 70% (HP) diets and hepatocytes were prepared from them. Rates of gluconeogenesis from pyruvate, alanine and threonine (10 mM) were unaffected by protein intake but 10 mM glutamine was converted faster by cells from HP fed animals. Rates of oxidation of alanine, threonine and glutamine and flux rates of tyrosine aminotransferase and tryptophan 2,3-dioxygenase were greater in cells from HP fed cats at all amino acid concentrations used. Proteolysis was indicated by urea production which was higher in cells from HP fed cats but was reduced significantly by leupeptin.
Article
Cats given DL-methionine (1 g/kg of body weight/day) developed severe hemolytic anemia with marked increase of methemoglobin (MetHb) concentration and Heinz-body formation at treatment-day 6 to 10. Cats fed 0.5 g of methionine/kg for 52 days had a moderate Heinz-body hemolytic anemia with methemoglobinemia at treatment days 17 to 31, but thereafter recovered from the anemia despite continuation of methionine feeding, indicating an adaptation of the cats. In vitro, significant (P less than 0.01) increases of MetHb concentration and Heinz-body formation were observed when RBC were incubated with plasma from cats fed (1 g of methionine/kg) or with 10 mM 3-methylthiopropionate, a product of methionine catabolism. However, these increases were not observed when RBC were incubated with 10 mM methionine. Seemingly, excessive methionine intake leads to production of an intermediate of the methionine catabolism that may affect RBC directly as an intensive oxidizing agent, resulting in an excessive oxidation of hemoglobin to MetHb and Heinz-body formation.
Article
Body proteins in cats were prelabelled with [14C]valine, and protein degradation was studied in isolated hepatocytes. Amino acids appeared to have a direct inhibitory effect on protein degradation, but the effects were generally smaller than those previously shown in the rat. The amino acid control of protein degradation in the cat differs from that in the rat, as shown by the lack of effects of glutamine, asparagine, arginine or methionine in cat hepatocytes. This may be related to the unique features of protein metabolism of this species. NH4Cl, leupeptin and amino acids, which suppress lysosomal protein degradation by different mechanisms, caused less than 30% inhibition of protein degradation when used at the optimum concentrations reported for the rat. The ability of the lysosomal system to respond to nutritional deprivation is apparently lower in the cat than in the rat.
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Body condition was assessed by owners and veterinarians for over 2000 cats presented to 31 private veterinary hospitals in the Northeastern United States. Each owner completed a questionnaire querying potential factors associated with his/her cat's body condition. Veterinarians reported twenty-five percent of cats were overweight (heavy or obese), while owners estimated 29% of their pets were overweight. Apartment dwelling, inactivity, middle age, being male, neutered, of mixed breeding, and certain dietary factors were associated with being overweight.
Article
To determine the association between body condition and disease in cats. Prospective study. Information on 1,457 cats without major illnesses from 27 veterinary hospitals in the northeastern United States. Cats that had body conditions determined from 1991 to 1992, using a set of 6 body condition silhouettes, had their health experiences and body conditions assessed for the subsequent 4.5 years. Cats were described by the following 6 body conditions: cachectic, lean, optimally lean, optimal weight, heavy, and obese. Data obtained from medical records and owner interviews were collected, using standard forms. Associations between body condition and specific diseases were analyzed. Findings in cats with body conditions other than optimal were compared with findings in cats with optimal body condition. Compared with optimal weight cats, heavy cats were 2.9 times as likely to be taken to veterinarians because of lameness not associated with cat bite abscesses. Obese cats were also 3.9 times as likely to develop diabetes mellitus, 2.3 times as likely to develop nonallergic skin conditions, and 4.9 times as likely to develop lameness requiring veterinary care. Cats considered thin (cachectic and lean) were 1.7 times as likely to be presented to veterinary hospitals for diarrhea. Results of this study substantiate reports of health risks associated with excess body weight in cats. Efforts to reduce weight in heavy and obese cats can lead to reduced risks of diabetes mellitus, lameness (presumably related to osteoarthritis and soft-tissue injuries), and skin problems unrelated to allergies. Cachectic and lean cats are more likely to have diarrhea that is not associated with a definitive diagnosis.
Article
Kittens fed diets containing 2.0 and 3.0 times (x) the NRC (1986) essential amino acid (EAA) requirement (EAArq) and 210 to 560 g crude protein (CP)/kg diet had growth rates and plasma amino acid patterns that were not significantly different than kittens fed a control diet (CD) containing 1.5 x EAArq and 350 g CP/kg diet. Growth rates of kittens fed diets containing only EAA (with nontoxic levels of arginine and methionine) and 280 to 460 g CP/kg diet were equivalent to those of kittens fed CD. Kittens fed only EAA and 140 and 210 g CP/kg diet had growth rates that were significantly lower than kittens fed CD. Since the growth rate of kittens fed 1.5 x EAArq and 210 g CP/kg diet in a previous experiment was equivalent to kittens fed CD (Taylor et al., 1997), it is suggested that the requirement for CP is higher (up to 280 g CP/kg diet) when only EAA are fed. The higher crude protein requirement appears to be primarily a consequence of the high obligatory nitrogen loss as urea (especially from arginine) incurred in the conversion of nitrogen from EAA to dispensable amino acids in the liver and secondarily because of a slow rate of catabolism of the EAA. A 3-dimensional plot of weight gains vs. CP levels and EAA to total nitrogen (E:T) ratios of kittens shows a broad range of CP levels and E:T ratios that support optimal growth in the kitten. It is suggested that similar patterns would occur in the chick, rat and other species if adverse effects caused by excesses of specific amino acids are avoided.
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